SFTP Error #3: Permission Denied – How to Fix

The default username format is:

SERVERNAME+username@SERVERNAME

Or edit the /etc/passwd entry as shown above to make the format simpler.

Here is a site I found useful for configuring Cygwin SSH:

https://dbaportal.eu/2015/03/05/installing-openssh-cygwin-1-7-35-on-windows-2012-r2/

You can try connecting using the verbose option:

ssh -vvv SERVERNAME+username@SERVERNAME

Check that the \home folders exist and permissions are correct for the user.

First... maybe this is not a good idea. It may be that the permissions are set this way to stop people from doing exactly what you are trying to do for some good reason. That said, you are the captain of your destiny.

Find out who can write to that dir. Do:

ls -ld /opt/myapp

and you will get something like:

drwxr-xr-x 6 myapp_user myapp_group 55 Sep 10  2016 /opt/myapp

Potential Option 1: switch to the user account that is built for that app. eg:

scp myfile myapp_user@example.com:/opt/myapp

But you likely do not have the password for that user. Potentially, you can solve that by authenticating with a key. https://www.techrepublic.com/article/how-to-use-secure-copy-with-ssh-key-authentication/

Potential Option 2: Change the permissions of the dir '/opt/myapp' to 774 (or 770)

chmod 774 /opt/myapp

Then make the admin user a member of the group that now has write permissions. https://www.howtogeek.com/50787/add-a-user-to-a-group-or-second-group-on-linux/ This one is not great as you may run into trouble with being blocked from over-writing files (depending on what is going on).